WASHINGTON (AP) -- The FBI and Homeland Security Department say there are no specific or credible terror threats to the U.S. homeland from the Islamic State militant group.

An intelligence bulletin, issued to state and local law enforcement, says while there's no credible threat to the U.S. as a result of recent American airstrikes in Iraq, officials remain concerned that Islamic State supporters could attack overseas targets with little warning.

U.S. law enforcement has been trying to identify Islamic State sympathizers who could help export the group's brand of violent jihad to the United States. U.S. airstrikes against the Islamic State group intensified after militants beheaded American journalist James Foley. The group called Foley's killing revenge for previous strikes against militants in Iraq.